Refer to the Following:
a Firm Sells Two Goods (X

Multiple Choice

Refer to the following:
A firm sells two goods (X and Y) that are related in consumption. The estimated demand and cost conditions are:
$$\begin{array} { l } P _ { X } = 20 - 0.1 Q _ { X } - 0.05 Q _ { y } \\P _ { y } = 70 - 0.3 Q _ { y } - 0.1 Q _ { X } \\M C _ { X } = 1 + 0.1 Q _ { X } \\M C _ { y } = 2 + 0.25 Q _ { y }\end{array}$$
-Goods X and Y are

A) complement
B) substitutes
C) independent
D) normal
E) inferior